In many industrial manufacturing processes, mechanical fasteners, such as rivets, screws, bolts and similar are used to connect or affix two or more objects together. The installation of such mechanical fasteners is often automated by machines or robots that can install mechanical fasteners much quicker and with a higher precision than a human being.
For such automated systems it is necessary to feed the mechanical fasteners quickly and reliably to the actual installation mechanism. This can be done by hand or by means of a supply magazine from which fasteners are gripped, whereas in most instances it is preferred to use appropriate feeder mechanisms. Such feeder mechanism feed the fastener to be installed either directly to the installation mechanism or to a gripping device which picks up the fastener from the feeder mechanism and moves it to another location for further processing or installation.
There are several objectives for such feeder mechanisms. First, they have to transport and feed fasteners in such a way that fasteners are not damaged in any way. Damaging of fasteners is a problem in particular in high speed applications, where a high number of fasteners have to be installed per time instance and are transported at high speeds by the feeder. Furthermore, in certain applications, like in aircraft construction, even slight defects of the fasteners due to the handling of the fasteners might have severe consequences, like impaired aerodynamics and stability. A second problem concerns the alignment of the mechanical fasteners. In automatic installation applications using e.g. a robot, the mechanical fasteners have to be fed to either the installation mechanism or to a gripping device in a defined way, which means in a defined orientation. Furthermore the transfer of the fastener from the feeder mechanism to the installation mechanism or gripping device must be reliable and the rate of tilted or misaligned fasteners must be as low as possible.
From prior art document DE 20 2008 014886 U1 a robot effector is known for installing mechanical fasteners, in particular rivets. Mechanical fasteners are fed to the robot effector from an external supply device via a hose or another transport means, in particular by means of pressurized air. Several types of mechanical fasteners may be stored in the supply device and may be selectively fed to the robot effector.